Arc generator



May 25,1926. 1,585,650

G. H. CLARK ARC GENERATOR Filed June 21'. 1922 kill v 'ssoasmcuax 351 his Gum; X

Patented May 25, 1926.

UNETEE STATES PATENT OFFI.

GEORGE H. CLARK, OF BROOKLYN, NEW YORK, ASSIGNOR TO RADIO CORPORATION OF AMERICA, A CORPORATION OF DELAWARE.

ARC GENERATOR.

Application filed June 27, 1922.

This invention relates to are generators of radio frequency for transmitting wireless signals.

When an arc is used for generating radio frequencies a large percentage of the energy supplied from the source of power is consumed in the formation of the arc and a certain amount is converted into useful radio frequency oscillations.

The object of the present invention is to increase the efliciency of a transmitter having an are as a generator or converter for producing high frequency oscillations from direct or low frequency alternating current.

To improve the operation and the efliciency of the are as an oscillation generator it is customary to provide one or more magnets excited by current from the source of power to provide a magnetic field for influencing the are.

I have found that the operation and particularly the eiliciency of the are when used for the purpose mentioned can be materially improved if radio frequency currents generated by the arc are passed through a coil in proximity thereto so as to create a rapidly varying magnetic field for influencing the arc. The radio frequency magnetic field may be advantageously superimposed on this field by having both windings on the same iron core or cores.

The single figure of the drawing illustrates diagrammatically one arrangement for carrying out the invention.

In the drawing, 1 represents an aerial; 2 is a loading coil; 3 and 1 are the electrodes of the are which are contained in an enclosure 5 which may be filled with hydrocarbin vapour in a well known manner. The source of energy is shown at 6, as a generator with an inductance 7 connected in series for preventing the passage of radio frequency currents thereto. Two diametrically opposite iron cores 8 and 9 and exciting coils 10 and 11 are shown in the drawing where the coil 2 is connected to one electrode 3 of the are which is also connected to a terminal of the generator. The other terminal of the generator is connected to the other electrode 4; with the exciting coils 10 and 11 in series in said connection.

Radio frequency currents from the arc may be caused to produce a field for influenc- Serial No. 571,248.

ing the are in accordance with the invention for example, as shown in the drawing where coils 12 and 13 are wound around the iron cores 8 and 9. In the illustration coils 12 and 13 are connected in series in the antenna circuit. by connecting coil 12 to electrode 4 and coil 13 to ground 14. Obviously, however, this arrangement is purely illustrative and not essential as the invention may readily be applied to circuit arrangements in which the output circuit of the arc is coupled to the antenna as well as other types of arc transmitting circuits.

The operation is the same as that of an ordinary arc transmitter except that in the modification illustrated high frequency cur rents flow through the coils 12 and 13 and produce a field for influencing the are which varies at the same frequency as the oscillations generated.

Having described my invention, what I claim is:

1. In an arc generator of high frequency currents, the combination of an arc and an oscillation circuit determining the frequency of the currents generated by the are, a source of current for feeding the are, means for producing a magnetic field for influencing the are, said means having a winding excited by currents from said source and another winding excited by said high frequency currents.

2. In combination, an arc, an oscillation circuit determining the frequency of the currents generated by the arc, a source of current feeding the are, means for producing a magnetic field for influencing the are, said means having a winding of large number of turns excited by currents through said are, and another winding of small number of turns excited by the current through said oscillation circuit.

3. In combination, an are, an oscillation circuit determining the frequency of the currents generated by the arc, a source of current feeding the arc, means for producing a magnetic field for influencing the are, said means having a winding of large number of turns excited by currents through said source, and another winding of small number of turns excited by the current througl said oscillation circuit, and located closer to said are than the first winding.

GEORGE H. CLARK. 

